IN-TIRE ELECTRIC DEVICE

To provide an in-tire electric device in which an electric circuit unit can be easily attached to a bracket and a force with which the electric circuit unit is held by the bracket has been increased than before. [0002] An in-tire electric device 101 of the present disclosure includes a bracket 10A fixed to an outer peripheral surface 96A of a rim 96 by a belt 90, and an electric circuit unit 50A detachably held by the bracket 10A. Then, through a two-step operation in which the electric circuit unit 50A is moved in a first direction and then rotated in a second direction, a first engagement protrusion 51 and a second engagement protrusion 52 of the electric circuit unit 50A are engaged with a first engagement hole 21 and a second engagement hole 22 of the bracket 10A, and thus a retainer 70A is engaged with the bracket 10A so that the reverse of the second direction is restricted.